Description: Any subset of the base set has an LUB in a complete lattice. (Contributed by NM, 14-Sep-2011)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | clatlubcl.b | |- B = ( Base ` K ) |
|
| clatlubcl.u | |- U = ( lub ` K ) |
||
| Assertion | clatlubcl | |- ( ( K e. CLat /\ S C_ B ) -> ( U ` S ) e. B ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | clatlubcl.b | |- B = ( Base ` K ) |
|
| 2 | clatlubcl.u | |- U = ( lub ` K ) |
|
| 3 | eqid | |- ( glb ` K ) = ( glb ` K ) |
|
| 4 | 1 2 3 | clatlem | |- ( ( K e. CLat /\ S C_ B ) -> ( ( U ` S ) e. B /\ ( ( glb ` K ) ` S ) e. B ) ) |
| 5 | 4 | simpld | |- ( ( K e. CLat /\ S C_ B ) -> ( U ` S ) e. B ) |